This invention relates to vibratory ground rollers of the kind having parallel rolling drums which are rotatably mounted in bearings in a main frame to which a steering frame provided with a seat for an operator is attached.
In one such vibratory ground roller, the main frame, in which the rolling drums rotate, has an extension at one end provided with a pin to which the steering frame is attached. The steering frame has wheels on a pivoted member acted upon by a pre-stressed hydraulic piston. The operator has to walk along by the side of the roller, which he steers by manipulating a handle on the steering frame. Control of the roller is tiring for the operator, particularly on uneven ground. In another known vibratory ground roller the steering frame has a seat for the operator. This makes his task easier and improves his control of the roller. However, all vibratory ground rollers have oscillation exciters which give the main frame, with its rolling drums, a pitching oscillation centered on the center of gravity of the main frame and the parts which it carries. Superimposed on the pitching oscillation there are further pitching movements produced by uneven ground and obstructions. The regular and irregular pitching movements of the main frame are transmitted through linkage connections to the steering frame, and consequently the operator, sitting on the steering frame, is subjected not only to vertical, that is to say heaving movements, but also to pitching movements.